<!DOCTYPE html>
<html>
    <head>
        <meta charset="utf-8">
        <title>margin.html</title>
        <style type="text/css">
            body{background-color: aqua;
            background-image: url(../qianduan-1/555.jpg);}
            .all{
                margin-top: 50px;
                margin-bottom: 50px;
                margin-left: 30px;
                margin-right: 30px;
            }
            .full-page-img{
                width: 100vw;
                height: 100vh;
                object-fit: cover;
                object-position: center;
            }
            .one{
                text-align: center;
                border-top-style: solid;
                border-bottom-style: solid;
                border-left-style: solid;
                border-right-style: solid;
                border-color: red;
            }
            .two{
                float: left;

                border-top-style: dotted;
                border-bottom-style: dotted;
                border-left-style: double;
                border-right-style: double;
                border-color:yellow;
            }
            .three{
                float: right;
                
                border-top-style: dashed;
                border-bottom-style: dashed;
                border-left-style:dashed ;
                border-right-style: dashed; 
                border-color:green; 
            }
            .four{
                text-align: center;
                border-style: solid; 
                border-width: 8px;
                padding: 5%;
                margin:3%;
                background-color: #ccc;
                border-color: #F00;
                border: 200px;
                height: 80px;
            }
            
        </style>
    </head>
    <body>
        <div class="one">
            <p>Div one需要设置为实现边框</p>
        </div>
        <div class="two">
            <p>Div two设计为上下点线，左右双实线</p>
        </div>
        <div class="three">
            <p>Div three设计为虚线</p>
        </div>
        <div class="four">
            <p>上述变化的颜色为红绿灯</p>
        </div>
    </body>
</html>